Conventional power conversion devices include for instance automotive power conversion devices mounted in electric cars or hybrid cars and in which an inverter device and a DC-DC converter device are integrated together.
Inverter devices and DC-DC converter devices ordinarily require cooling. Therefore, in many cases, a refrigerant channel, through which refrigerant for cooling flows, is formed inside a case within which the inverter device or the DC-DC converter device is disposed. Cooling structures have been disclosed wherein refrigerant channels are provided inside a C-shaped case, and for instance inductor elements and power semiconductor modules that generate comparatively large amounts of heat are disposed in the vicinity of the refrigerant channels, to increase thereby cooling efficiency (see for instance PTL 1).
Structures have also been disclosed in which flow channels are provided along heat dissipation surfaces on both surfaces of semiconductor modules, and cooling water is supplied to the flow channels, to increase thereby cooling efficiency (see for instance PTL 2).